A reaction between benzene and propylene gives cumene. Oxidation of cumene results in cumene hydroperoxide. The cumene hydroperoxide is acid decomposed into phenol and acetone. A combination of these known reactions is the cumene process and is currently a mainstream process for the production of phenol.
In the cumene process, acetone is byproduced. The cumene process is valuable when both phenol and acetone are required. However, if the acetone produced is in excess of demand, the economic efficiency is deteriorated due to the price difference between acetone and starting material propylene. Methods have been then proposed in which acetone byproduced is reused as a material in the cumene process through various reactions.
Acetone is readily hydrogenated to isopropyl alcohol, and the isopropyl alcohol is dehydrated to propylene. Patent Document 1 discloses a process in which acetone is reused as a material in the cumene process, in detail cumene is produced by reacting benzene and propylene obtained from acetone as described above.
In the reuse of acetone, an industrial and practical process should be established which is capable of producing propylene from acetone with high selectivity. Further, the establishment of industrial and practical processes capable of producing not only propylene but other olefins from general ketones with high selectivity is also valuable in various other processes.
Patent Document 2 discloses a process in which propylene is obtained through hydrogenation of acetone at 400° C. in the presence of a catalyst containing Cu (25%), zinc oxide (35%) and aluminum oxide (40%). However, this process involves high reaction temperature and is insufficient in heat efficiency.
Patent Document 1: JP-A-H02-174737
Patent Document 2: East German Patent DD84378